We have used SoundScout Automated Recording Units since 2016 as a non-invasive method to survey for four sensitive raptor species – Northern Goshawk, Great Gray Owl, Boreal Owl, and Flammulated Owl – in Wyoming. Through the development of species-specific detectors, and by using cluster analysis in the Kaleidoscope software, we have been able to detect these species more efficiently from countless hours of audio recordings and identify active territories. This method has allowed us to conduct sensitive raptor species surveys for the Bridger-Teton National Forest’s Teton to Snake Fuels Management Project and annually monitor for active territories of several forest raptor species.
In 2019 we completed a project in northwest Wyoming to assess the effectiveness of using autonomous recording devices to accurately survey for occupied Northern Goshawk territories. In comparison to traditional call playback surveys we found that the use of autonomous recording devices, which detect daily pre-dawn vocalizations of breeding goshawks, was more effective for detecting active goshawk territories. We have been utilizing this method to locate and monitor active goshawk territories across northwest Wyoming.
By deploying Automated Recording Units across northwestern Wyoming in known Great Gray Owl territories since 2016, we have amassed thousands of territorial calls from dozens of individuals. We are in the process of determining how to effectively utilize Great Gray Owl calls to identify individuals on territories over the years based on differences in territorial call characteristics. Our ultimate goal is to utilize these methods to better understand Great Gray Owl population dynamics and movements between territories without the need to tag individuals with transmitters.